AMD XC3S400AN-4FTG256I

Overview

XC3S400AN-4FTG256I from AMD (formerly Xilinx) is a Spartan-3AN FPGA with 400,000 system gates, 216 I/O pins, and integrated flash memory for single-chip configuration. It features 8,064 logic cells, operates at -4 speed grade (1.11 ns CLB delay), and supports 3.3 V/2.5 V/1.2 V I/O standards. Used in industrial control modules requiring reconfigurable logic and nonvolatile configuration storage.

For engineers reviewing the XC3S400AN-4FTG256I datasheet, pinout, applications, or equivalent options, key selection criteria include embedded flash capacity, I/O voltage flexibility, CLB timing performance, and industrial temperature range support.

Technical Context

The XC3S400AN-4FTG256I integrates 4-Mbit on-chip flash memory enabling instant-on operation without external configuration PROMs. Its architecture includes dedicated digital clock managers (DCMs) supporting frequency synthesis, phase shifting, and duty-cycle correction across up to 4 independent clock domains.

It implements SelectIO technology with programmable drive strength (2–24 mA), slew rate control, and on-die termination (ODT) for 3.3 V, 2.5 V, and 1.2 V I/O standards. Configuration occurs via JTAG or master serial mode using the internal flash.

Key Specifications

Pinout & Package

XC3S400AN-4FTG256I is housed in a 256-pin Fine-Pitch Thin Quad Flatpack (FTBGA) package with 1.0 mm pitch and 17 × 17 mm body size. Pin assignments follow Xilinx Spartan-3AN family standard ballout, with dedicated configuration, clock, JTAG, and dual-voltage I/O banks.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar FPGA configuration and logic implementation applications.

Compared with XC3S400AN-4FTG256I, the XC3S500AN-4FTG256I offers scalable logic headroom in identical packaging, while the XC6SLX45-3CSG324I trades flash integration for advanced peripherals and higher density-requiring layout and firmware changes for migration.

Availability

XC3S400AN-4FTG256I is available at Aetrix Electronics and suitable for industrial PLC I/O modules, motor control interface boards, and factory automation sensor hubs requiring stable component supply and long-term obsolescence management.

Supply support for XC3S400AN-4FTG256I includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

AMD acquired Xilinx in 2022 and continues development and support of the Spartan FPGA product families for cost-sensitive, high-volume industrial applications.

The Spartan-3AN series was designed specifically for embedded applications requiring nonvolatile configuration, instant-on operation, and robust I/O flexibility in extended temperature environments.

FAQ

What is the operating temperature range for XC3S400AN-4FTG256I?

The XC3S400AN-4FTG256I is rated for industrial operation from −40°C to +100°C. This range is verified per Xilinx specification DS229 and applies to all I/O banks, configuration circuitry, and logic fabric under specified voltage and loading conditions. The XC3S400AN-4FTG256I maintains timing compliance across this full range when used with the -4 speed grade.

Does XC3S400AN-4FTG256I require an external configuration PROM?

No, the XC3S400AN-4FTG256I contains 4 Mbit of integrated flash memory and supports autonomous configuration at power-up. External PROMs are optional only for field updates via JTAG or fallback configurations. The XC3S400AN-4FTG256I eliminates the need for external configuration memory in most deployments.

Can XC3S400AN-4FTG256I operate with mixed I/O voltages?

Yes, the XC3S400AN-4FTG256I supports mixed I/O standards across its eight configurable I/O banks. Each bank can be independently set to 3.3 V, 2.5 V, or 1.2 V operation using VCCO pins. This capability is documented in the Spartan-3AN Hardware User Guide UG380 and applies directly to the XC3S400AN-4FTG256I.

How many Digital Clock Managers (DCMs) does XC3S400AN-4FTG256I include?

The XC3S400AN-4FTG256I includes two fully functional Digital Clock Managers (DCMs). Each DCM supports input clock multiplication, division, phase shifting, and duty-cycle correction. These DCMs are accessible to all clock-capable pins and are integral to the XC3S400AN-4FTG256I's timing architecture.

Is XC3S400AN-4FTG256I pin-compatible with other Spartan-3AN devices in FTG256 packaging?

Yes, the XC3S400AN-4FTG256I shares identical pinout and package dimensions with other Spartan-3AN devices in the 256-pin FTBGA (FTG256) package, including XC3S200AN-4FTG256I and XC3S500AN-4FTG256I. Signal routing and PCB layout are interchangeable across these variants, as confirmed in Xilinx Package Outline Drawing DS117.